1. Field of the Invention
The present invention relates to a detection device and an insertion portion detection system which detect an insertion amount of an insertion portion having a cylindrical shape, and an amount of rotation around the central axis of the cylindrical shape.
2. Description of the Related Art
In general, it is necessary to detect an insertion amount when inserting an insertion portion of, for example, an endoscope device into an insertion target. For example, Jpn. Pat. Appln. KOKAI Publication No. 2005-185308 has suggested a system comprising at least a roller disposed in an insertion assist tool, and a sensor which detects the number of rotations of the roller, to detect the relative amount of the insertion of the insertion portion into the insertion assist tool.
In this configuration, the roller rotates while being in contact with the outer circumferential surface of the insertion portion, and the number of rotations of the roller is detected to calculate an insertion amount. As another embodiment, there is also a description of a system in which optical indexes or magnetic indexes are attached to the insertion portion and are read by an optical sensor or a magnetic sensor to detect an insertion amount.